Treatment of nongelatin emulsions



aiented June 194 5 John I. Crabtree and Geo N. Y., assignors to" Rochester, N. Y.,

No Drawing.

rge 'lJEaton, Roehester, Eastman Kodak Co a corporation or New Jersey Application October 16, 1942,

Serial No. 462,232 6 Claims. (CI. 95-88) This invention relates to improved photographic procedure for the treatment of nongelatin photographic elements, and in particular to procedure for removing opalescence from photographic elements bearing a non-gelatin layer.

Various resin products which act as protective colloids or carriers have been proposed as a substitute for gelatin in photographic emulslons. Thus, resins such as cellulose nitrate, acetate, acetate-butyrate; polyvinyl acetals such as polyvinyl-acetaldehyde acetal and polyvinyl butyraldehyde acetal; cold water soluble polyvinyl acetaldehyde acetal: polyvinyl alcohol; and polyvinyl esters such as h'ydrolized vinyl acetate, have been used for this purpose. These substitutes are superior to gelatin in many respects, but it has been noted that with certain developing and fixing solutions or with certain forms of these'gelatin substitutes a photographic element. is obtained which isopalescent. The opalescence is apparently caused by the process- 5 supplemental bath just prior to washing.

We prefer to utilize the opalescent removing agents in aqueous solution in the following proportions:

Per cent solution Ethylenediamine 1 to 60 Ethanolamine 1 to 25 Triethanolamine 1 to 20 Alcohol 1 to 70 However, these proportions can be varied considerably and it is to be understood that our invention is not limited thereto. After treatment with the opalescent removing agent the photographic element is permitted to dry or is preferably first washed with water and then log baths and is produced when the element comes in contact with the wash water. The element remains opalescent to a lesser degree when dry. g

This invention has for-its object to'provide H procedure for removing this opalescence. An-

other object is to provide procedure for removingthe opalescence from processed non-gelatin emulsions. Other objects will appear hereai'ter. These and other objects are accomplished by our invention which includes preventing or removing opa escence by treating the photographic element bearing a non-gelatin layer with a solution containinga member of the group consisting of ethylenediamines. ethanolamine, trietlranolamine and alcohol. In-the following examples and description we have given several of the preferred embodiments of our invention,- but it is to be understood that these are set forth for the purpou or illustration and not in limitation thereof.

It is preferred that the photographicelement be treated with the substances mentioned imdried.

Our invention is applicable to the treatment of non-gelatin emulsions in general. However, it is 01 particular value in connection with the 2 treatment of emulsions containing a cellulose ester carrier containing between about 26 and 33% acyl and of polyvinyl resins, particularly polyvinyl acetal resins.

' Example A film carrying an emulsion of silver halide in a cellulose acetate-propionate carrier (22.5%

acetyl and 17.0% proplonyl) was exposed, developed,' iixed andwashed in the usual manner.

35 -When introduced into the washing bath the illm 4o sulted in a clear fllm on drying.

became opalescent and remained so to a lesser degree when dried. The use of a supplemental bath immediately following fixing and contain-' ing 25% ethanolamine in aqueous solution re- What we claim is:

1. The method or removing opalescence iro a photographic'element which comprises treating the opalescent ;.hotographic element bearing a non-gelatin layer containing a developed and mediately alter such as immediately alter develop z, fixing and/or washing. 0n the other hand much the same-results can be obtained if the photographic element is maintained in a wet condition after the processing treatment and is treatedto remove the opalescence at any subsequent time. It ha been found that it the photographic element is first permitted to dry the coalescent quality is more dimcult to remove. However. it is to be understood that our invenopalescence in; a photographic element which Q silver image with a solution or a member ,0! the group consisting of ethylenediamine, ethav nolamine, triethanolamine and alcohol.

2. The method of preventing or removing comprises treating the photographic element bearing a non-gelatin layer containing a silver image with a solution containing a member 01' the group consisting of ethylenediamine, ethanolamine, triethanolamine and alcohol.

3. The method of preventing or removing opalescence in' a photographic element which comprises treating the photographic element bearing a cellulose ester layer containing a developed and fixed silver image with a solution containing a member of the group consisting of ethylenediamine, ethanolamine, triethanolamine opalescence in a photographic element which comprises treating the photographic element bearing a .polyvinyl resin layer containing a developed and fixed silver image with a solution containing a member of the group consisting of ethylenediamine, ethanolamine, tricthanolamine and alcohol.

6. The method of preventing or removing .opalescence in a photographic element which comprises treating the photographic element bearing a polyvinyl acetal layer containing a developed and fixed silver image with asolution containing a member of the group consisting of ethylenediamine, ethanolamine, trlethanolamine and alcohol.

JOHN I. CRAB'I'REE. GEORGE T. EATON. 

